The present invention relates to a continuous process for making high-solids confectionery products containing agar-agar utilizing high temperature short time processing.
Agar-Agar is a complex mixture of polysaccharides which are extracted from red seaweed. All components of the mixture contain the same backbone structure composed of alternating monosaccharide units of D-galactose and 3,6 anhydro-L-galactose. Some of the polysaccharide chains are substituted to a variable degree with charged groups, namely sulfate, pyruvic acid and uronic acid.
Agar-Agar is the least soluble of all of the polysaccharide gelling agents. It is virtually insoluble in cold water, slightly soluble in hot water and readily soluble in boiling water. It forms a strong brittle, turgid gel when hot aqueous dispersions of same are prepared and cooled.
The melting and setting properties of agar-agar display hysteresis, i.e., agar-agar jellies melt at 80xc2x0-90xc2x0 C. (176xc2x0-194xc2x0 F.) , yet they set at 30-40xc2x0 C. (86xc2x0-104xc2x0 F.). Such properties are obviously useful when depositing hot products into molds, for there is little or no risk of premature setting or pre-gelling.
Agar-agar is used in various foods, such as baking icings, no oil salad dressings and low fat yogurt.
It can also be used in many confectionery products, especially in gums and jelly products, marshmallows and the like, as a gelling agent. It is usually present in small amounts, typically ranging from 0.2% to 1.8% by weight.
One of the drawbacks of using agar-agar is that it requires a large quantity of water to make a good solution and an aqueous dispersion. Typically, it requires 30-50 times its weight in water to make an aqueous solution of same. For example, standard methods for using agar-agar in confectionery products recommend hydrating the agar-agar for several hours, usually at least 12 hours, in at least a 30:1 ratio by weight of water to agar-agar, or a short-time boiling, usually 3-5 minute boil, of the agar-agar in water at the aforementioned ratio, to fully hydrate the gum for incorporation into the high solids confectionery product. This extensive hydration time that is required makes it unattractive for use in a continuous process or in automated plants. As a result, although found in confectionery products, its use is limited to batch type operations.
Moreover, it is widely held in the confectionery industry that agar-agar cannot be used in a continuous process in which it is subjected to high temperatures. It is commonly believed in the food arts that one of the drawbacks of agar-agar is that it cannot be subjected to the high temperatures required for solubility of various components by normal pasteurization or pasteurization-like processes. Subjecting the food containing agar-agar to high temperatures has been shown to be detrimental in many food applications, e.g., the food loses its flavor or develops off-flavor.
Furthermore, since agar-agar is used in a batch process, rather than a continuous process, there are further drawbacks to its use.
A batch process is generally more expensive, more inefficient and more labor intensive than a continuous process, especially in making high solids confections. In an example of the batch process for making high solids confectionery products, an aqueous solution of sucrose is mixed with corn syrup and other ingredients in a large kettle at a concentration of about 60 to 75% solids. The solution is cooked in this kettle. The solution is normally cooked at atmospheric pressure to concentrate the product to about 85 percent solids. The solution is then cooled to about 70xc2x0 C.-45xc2x0 C. (158xc2x0 F.-113xc2x0 F.).
The above described batch method often requires multiple mixing steps and transferal of the various intermediate products prepared after each step of the process from various production apparatus and work areas until the final product is produced. These operations are not performed continuously, but batchwise. Batch processes usually require more equipment than continuous processes, and they are usually less efficient. Moreover, since the batch process is non-continuous, the various mixing steps require the continuous input of operators in order to adjust the processing parameters, resulting in the batch process requiring more manual labor relative to continuous processes.
Thus, batch processes are generally slower than continuous processes, require substantial amount of manual labor and are consequently more expensive. It also introduces a number of opportunities for error, resulting, for example, in poor or wasted batches, as the result of mis-measurement, overmixing and the like.
On the other hand, a continuous process for making high solids confectionery products has several advantages relative to a batch process. As the name suggests, a continuous process involves a continuous mode of operation. In a continuous process, automated equipment is used so that the entire process is run continuously. As soon as a vessel is emptied, it is immediately filled with, in the case of high solids confectionery, a mixture of the ingredients to be processed. By xe2x80x9ccontinuousxe2x80x9d, as used herein, it is meant the mixture is introduced over an extended period of time either as a flowing stream or as a series of spaced apart portions. However, as used herein, a continuous process also includes the situation wherein the additions of the ingredients to form the uncooked mixture is performed manually or by other batch-wise means. In other words after the majority of the ingredients, i.e., gelling agent, water and sweeteners are added to the appropriate tank or apparatus, and mixed, the process is continuous thereafter. In a continuous process, the various apparatus and equipment used in the process are in fluid communication with one another. Thus an embodiment of a continuous process for making high solid confectionery contemplates adding the sugar solution and corn syrup in predetermined amounts and in measured volumes to a mixer to form a homogenous solution, introducing the solution as a flowing material into the various apparatus used in the process, such as other mixers or heaters, through inlet valves automatically and continuously or at predetermined spaced intervals, continuous removal of intermediate products from mixers and heaters through exit valves, automatically and continuously introducing the heated solution into coolers, etc. Thus, the entire process is performed continuously, with little, if any, stoppage. Thus, there are several advantages of the continuous process relative to the batch process, such as shorter processing time, reduced labor, reduced amount of material used and less cost. In consequence, modern food plants primarily utilize continuous manufacturing methods and installed equipment to effectuate such processing, incorporating high temperature short time processing steps.
Because of the problems referred to hereinabove, it has been disadvantageous heretofore to use agar-agar in high solids confectionery products. In general, high solids confectionery products prepared by a continuous process, especially those products which utilize gelling agents or have chewy characteristics, utilize other hydrocolloids. One of the most common hydrocolloids used is gelatin. High solids confections containing gelatin are produced by the continuous process, and the products produced are quite satisfactory to the public; they are stringy and chewy and, if necessary, they can be aerated to produce a marshmallow or marshmallow-like texture.
However, there are a number of disadvantages utilizing gelatin. One disadvantage is that since it contains protein, gelatin must be added after the cooking step; if added before cooking, it will denature. Moreover, there is an increased risk of microbial problems, especially if the solution containing gelatin is stored for an extended period of time. Furthermore, gelatin is prepared from collagen which is present in skins, bones, hides and connective tissues from animals. It is, therefore, generally non-kosher since, in most cases, the animal is not properly killed. Although Kosher gelatin is available, it is not only extremely expensive, but in addition, it is difficult to obtain a constant supply since availability is limited.
Thus, although gelatin is attractive since it has been used in preparing high solids confectioneries, it is also unattractive for the reasons given hereinabove, but especially because of the commercial reality that certain portions of the population may not purchase products containing non-kosher gelatin and the enhanced risk of microbial problems.
Thus, the problem was to find another gelling agent to replace gelatin which can be used in preparing high solid confectionery products by a continuous process, and which would impart the necessary chewy characteristics, stringiness and gelling properties to the confection.
The task was not simple. When the present inventors used other gelling agents instead of gelatin to prepare high solid confectionery products by a continuous process, the products containing them were inferior to the gelatin containing products. The confection products containing a gelling agent other than the gelatin did not exhibit the stringiness or chewy characteristics that are found in jellies, gum or other high solids confectionery products containing gelatin.
The present inventors also attempted to make high solid confectionery products utilizing new speciality products which have been developed in recent years which are also useful as gelling agents. These are referred to as xe2x80x9cquick soluble agarsxe2x80x9d, and they are physically modified agar-agar to permit hydration at temperatures below boiling, i.e. 60-80xc2x0 C. Therefore they have several advantages, such as easy preparation, less preparation time and application to continuous cooking. However, the quick soluble agars require further processing of the agar-agar by the supplier and are very expensive. For these reasons, these quick soluble agars seemed unattractive. Furthermore, when used in attempts to make high solid confectionery products, it hydrates before cooking resulting in the pre-cooked product being more viscous. Consequently, it is more difficult to work with, for example, it exhibits less efficient heat transfer during cooking and it is more difficult to pump than if the mixture contained other hydrocolloids or, as shown hereinbelow, agar-agar.
The present inventors then focused on agar-agar. Since it is made from plants, it is kosher. However, due to its properties described hereinabove, it was never used heretofore in preparing high solids confectionery products in a continuous process. In order to use agar-agar in a continuous process, the present inventors needed to find a solution to circumvent the extensive pre-hydration procedures referred to hereinabove.
Thus, the present inventors searched for a method of using natural agar-agar in a continuous process for making high solids confectionery using high temperature and short time processing.
They finally found a solution. More specifically, they found that by mixing an agar-agar dispersing agent with agar-agar in the appropriate amounts, they could prepare high solids confectionery in a high temperature, short time continuous process without the need for the extensive pre-hydration procedures described hereinabove.
Accordingly, the present process is directed to an improved method for making a high solids confectionery product in a high temperature short time continuous process in which a homogenous mixture comprising a sweetener, agar-agar, and water is heated under cooking conditions; concentrating the cooked mixture by removing water therefrom; and then cooling the concentrated mixture, the improvement comprising (a) prior to cooking, mixing said homogenous mixture with an agar-agar dispersing agent under conditions sufficient to form a homogenous mixture, said agar-agar dispersing agent being present in an amount sufficient to control the hydration of the agar-agar; and (b) conducting the process as a continuous process and cooking the mixture under high temperature short time conditions.
The present process is also directed to a method of making a high solids confectionery product in a continuous process which comprises:
(a) preparing a homogenous mixture comprising agar-agar, an agar-agar dispersing agent in an amount sufficient to control hydration of agar-agar when water is added thereto, a sweetening effective amount of a sweetener, and water, said homogenous mixture containing a solids content ranging from about 60% to about 80% by weight solids;
(b) feeding the homogenous mixture of step (a) to a heating apparatus having an inlet and an outlet with heating means interposed therebetween and subjecting said mixture to a high temperature short time continuous process under conditions sufficient to cook and concentrate the mixture; and
(c) removing the formed water vapor therefrom and cooling said cooked mixture, thereby forming said high solids confectionery product, all aforesaid steps being conducted substantially continuously in said continuous process.